Mounting of panels in screening apparatus can present problems both in initial installation and in removal and replacement of worn panels and these problems become particularly acute when the apparatus is vibrating screening apparatus. Such apparatus customarily has a grid or frame bounded at sides by side plates and for each of one or more decks or levels either laterally spaced longitudinal or intersecting longitudinal and transverse support members.
To be both installable and removable, the screen panels in vibrating screening apparatus must be removably fastened to the support members. The present practice in fastening systems for vibrating apparatus is to fasten the panels directly to the support members by fasteners inserted in the panels and received in apertures or holes in the support members. The fasteners used or proposed for such systems are of several types. In one type, disclosed in the Freissle, U.S. Pat. No. 3,980,555, the fasteners are half-round frusto-conical plastic plugs or protusions integral and flush with and depending from sides of a molded polyurethane screen panel, each insertible with a half plug of an adjoining panel in an aligned aperture in a support member.
In the system disclosed in the Wolff, U.S. Pat. No. 4,141,821, the screen panels, molded or cast suitably of polyurethane, have integral hollow tubular sleeves or protrusions seatable in apertures in support members and expandable into clamping contact with the apertures by individual metal or plastic pins inserted through the protrusions. In the modification of FIG. 8, Wolff replaces the separate pins of his preferred embodiment by a plurality of necked frusto-conical pins molded to a rib separate from a screen panel and insertible together through tubular protrusions in a panel. Another present fastening system dispenses with integral tubular sleeves or protrusions on the screen panels and uses for fastening a suitably polyurethane securing pin having a head seatable in an opening in a panel and a neck restricted to fit an aperture in a support member.
The present invention is an improvement on prior systems for mounting screen panels in vibrating and other screening apparatus.